// Copyright (c) 2009-2011, Tor M. Aamodt, George L. Yuan
// The University of British Columbia
// All rights reserved.
//
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions are met:
//
// Redistributions of source code must retain the above copyright notice, this
// list of conditions and the following disclaimer.
// Redistributions in binary form must reproduce the above copyright notice,
// this list of conditions and the following disclaimer in the documentation
// and/or other materials provided with the distribution. Neither the name of
// The University of British Columbia nor the names of its contributors may be
// used to endorse or promote products derived from this software without
// specific prior written permission.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
// AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
// IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
// ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
// LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
// CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
// SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
// INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
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// ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
// POSSIBILITY OF SUCH DAMAGE.

#include "gpu-misc.h"

unsigned int LOGB2(unsigned int v) {
  unsigned int shift;
  unsigned int r;

  r = 0;

  shift = ((v & 0xFFFF0000) != 0) << 4;
  v >>= shift;
  r |= shift;
  shift = ((v & 0xFF00) != 0) << 3;
  v >>= shift;
  r |= shift;
  shift = ((v & 0xF0) != 0) << 2;
  v >>= shift;
  r |= shift;
  shift = ((v & 0xC) != 0) << 1;
  v >>= shift;
  r |= shift;
  shift = ((v & 0x2) != 0) << 0;
  v >>= shift;
  r |= shift;

  return r;
}
